| 摘要 |
PROBLEM TO BE SOLVED: To provide high purity ruthenium at a high yield.SOLUTION: Regarding a method in which ruthenium in a ruthenium-containing acidic solution is oxidized into volatile ruthenium tetraoxide by oxidation reaction, and is distilled to recover ruthenium, the oxidation reaction is performed in such a manner that the ruthenium-containing acidic solution is added to an oxidizer solution comprising an oxidizer by an amount more than an equivalent required for the oxidation reaction, and the oxidation reaction is performed. Further, it is performed, in a reaction liquid obtained by adding the ruthenium-containing acidic solution to an oxidizer solution, in such a manner that the ruthenium tetraoxide is not phase-separated in the reaction liquid while regulating the concentration of ruthenium tetraoxide in the reaction liquid. The precipitation of ruthenium dioxide upon distillation, the phase separation of the ruthenium tetraoxide by the distillation of ruthenium tetraoxide in a reaction tank 1, the increase of the pH of the oxidizer solution upon the oxidation reaction, and the intrusion of impurity metals into absorption tanks 6a, 6b or the like can be solved. |
